Well I am not that familiar with the SSW's power level, but on the folowing scale a normal human rates a 1 while Superman rates a 10. Juggey would rate around an 8 (7.5 to 8.5). So it then depends on how you define "beat".
Could Olga do to Juggernaut what The Guardian did in the X-Men animated series (pick him up 1 handed and toss him like yesterdays trash into another timezone) most likely. But even throwing him into space only delays him until he re-enters and after he gets out of his crash site boy will he be mad.
Can she pummel him to the point where he is truely defeated and unable to do much more than breath? Unless she rivals Superman in strength AND invulnerability, not likely.
Oh and my above comparison does take into account that Superman can carry somewhere around 855,000 tons while Juggernaut is limited to carrying only around 100 tons (purely for a strength vs strength comparison).
Pehaps giving him a quick ride into orbit would do the trick.
This is a GREAT version of Olga, very, very muscular yet not overly huge.
"Nothing can stop the Juggernaut!" or so we've been told. But we've seen that a new foundation for a building full of wet concrete can slow him down a lot!
If she fights smart, which we know she can do.
Brute force is not going to do it, she'll never beat Juggernaught that way. Hitting him is useless, so she'll just have to find some other way to get rid of him.